Automatic box-wrapping system for loose-wrap and tight-wrap work



3,045,561 -WRAP R. SCHEMPP AUTOMATIC BOX-WRAPPING SYSTEM FOR LOOSE AND TIGHT-WRAP WORK July 24, 1962 5 Sheets-Sheet 1 Filed May 20, 1960 July 24, 1962 R. SCHEMPP 3,045,561

AUTOMATIC BOX-WRAPPING SYSTEM FOR LOOSE-WRAP AND TIGHT-WRAP WORK Filed May 20, 1960 3 Sheets-Sheet 2 July 24, 1962 R. SCHEMPP 3,045,561

AUTOMATIC BOX-WRAPPING SYSTEM FOR LOOSE-WRAP AND TIGHTWRAP WORK Filed May 20, 1960 3 Sheets-Sheet 3 United States Patent Ofiiee 3,045,561 Patented July 241, 1962 This invention relates to an automatic box-wrapping system and has for an object the provision of a boxwrapping system suited for the loose-wrap or tightwrap of set-up boxes.

The term set-up box is used in the art to designate box blanks which have been formed with vertical walls and the corners formed by the ends of adjacent walls having stays or other suitable attaching means secured thereto for holding the walls in upright position. These set-up boxes are then assembled with a wrapper and depending upon the adhesive pattern on the wrapper, the resulting wrapped box is of either loose-wrap or tight-wrap character. For tight-wrap work, the wrapper is provided with an overall coat of adhesive so that all portions of the wrapper adhere to the set-up box surface. For loosewrap work, the adhesive pattern on the wrapper is such that the adhesive is only applied around the edges of the wrapper so that only the portions of the wrapper which extend inside of the box are adhesively secured to the box. The portions of the Wrapper which extend over the side walls and bottom of the box are not adhesively secured thereto; in other words, they are loose and hence the term loose-wrap is used to designate this type of work. In the box-making trade, some customers prefer tight-wrap work, while others prefer loose-wrap work and in view of the fact that automatic box-wrapping equipment is relatively expensive, it is desirable that the same equipment be adapted for turning out both types of work. In addition, loose-wrap work generally provides a better-appearing finished box and at a lower manufacturing cost in view of the fact that less adhesive is required on the wrapper.

The present invention is an improvement upon the full automatic systems of the prior art, such for example as the full automatic system disclosed in Andresen Jr. et al., United States Patent 2,867,158.

In accordance with the present invention, there is provided an automatic box-wrapping system suited for loosewrap or tight-wrap o-f set-up boxes. This system includes a box conveyor for cyclically moving set-up boxes in succession along a path. A wrapper conveyor cyclically feeds adhesive-coated wrappers in succession along the path and below the box conveyor. A pair of cyclically operable reciprocating plunger means are disposed at spaced stations along the path and there is means for interrupting the movement of each leading wrapper when the transverse center line of the wrapper is in alignment with the transverse center line of the selected one of the spaced stations. The system further includes means for operating the reciprocating plunger means at the selected one of the spaced stations for successively moving the leading boxes downwardly into register with the corresponding leading wrappers at the selected one of the stations and for rendering inoperative the other of the plunger means. At the second of the stations there is transfer means movable transversely of the path for transferring each registered set-up box and wrapper in succession from the second station to a wrapping station where the adhesive-coated wrapper is applied to the setup box to provide a loose-wrap or tight-wrap box depending upon the adhesive pattern on the wrapper.

For a more detailed disclosure of the invention and for further objects and advantages thereof, reference may be had to the following description taken in conjunction with the accompanying drawings in which:

FIG. 1 is a front elevation of an automatic box-wrapping system embodying the present invention;

FIG. 2 is a top plan view of 'FIG. 1;

FIG. 3 is a perspective view of the box support and box plunger of the registering device at the transfer station;

FIG. 3A is a fractional view of the operating mech- I anism for the box plungers at the registering stations;

FIG. 4 is another perspective view of the transfer station of a box and wrapper assembly about to be transferred from the transfer station to the wrapping station;

FIG. 5 is a perspective view of the box and wrapper assembly in transit from the transfer station to the wrapping station;

FIG. 6 is a fractional side view of the transfer mechanism for the wrapper; and

FIG. 7 is a fractional end view partly in section taken along the lines 77 in FIG. 6.

Referring to FIGS. 1 and 2, it will be seen that in many respects, the present box-wrapping system 10 is generally similar to the automatic box-wrapping system disclosed in the aforesaid Andresen Jr. et al. patent. As in the case of the Andresen Jr. et al. system, the present system includes as components thereof a stayer S, a box conveyor BC, a gluer G, a suction conveyor C for the wrappers, a box-registering device R and a box-wrapping machine M. In addition, the present invention includes a second box-registering station R and an extension BC, for the box conveyor BC extending between the two box-registering stations R and R All of these components are cyclically operated in timed relation with a main cam 8 attached to a vertical shaft 9 which is motor driven. The various components of the present boxwrapping system which correspond to those in the Andresen Jr. et al. Patent 2,867,158 are of similar construction and operation and thus it is not believed necessary to elaborate upon their details here as their description is hereby incorporated herein by reference thereto. I The present invention will first be described in connection with loose-wrap work. Box blanks b are fed to the staying machine S from a stack of blanks b in FIGS. 1 and 2. The staying machine S is illustrated as a quad stayer and thus stays s are applied to the four corners of the box concurrently. The box blanks b thus automatically are transformed by the stayer S from blanks b in the flat to stayed set-up boxes B. As they leave the staying machine S, the set-up boxes B are delivered in succession from the staying machine onto the box conveyor BC and continue in a straight line beneath the registering device R and onto the extension BC of the box conveyor until the leading box arrives at a position underneath the plunger P of the second box-registering device R The plunger P forces the leading box B downwardly into register with the leading wrapper W which has been previously coated with a predetermined adhesive pattern and fed by cooperation of the gluer G and the suction conveyor C to the combined assembly station and transfer station directly beneath the plunger P The adhesive-coated wrapper W is moved into a position beneath the plunger P against an end stop B such that the center lines of the wrapper will be in alignment with the center lines of the box B to be assembled therewith. Thereafter the assembly, comprising an adhesivecoated wrapper in the flat and set-up box registered thereon, is moved from the transfer station at the end of the suction conveyor C to the Wrapping station of the boxwrapping machine M which is directly opposite the transfer station and where the wrapper is adhesively applied to the box.

As may be seen in FIGS. 1 and 2, the extension BC,

of the box conveyor preferably includes an endless belt 11 which passes over a pair of spaced rollers 12 and 13 which in tum are supported from the frame of the suction conveyor C. The roller 12 is provided with a sprocket wheel 14 over which passes a sprocket chain 15 which in turn passes around a sprocket wheel 16 driven from the main box conveyor BC. At the registering station R and supported at the end of the extension BC of the box conveyor there is provided box-supporting structure similar to that disclosed in the aforesaid Andresen Jr. et al. patent (FIG. 8) and also utilized at the first register station R in the present system 10. As shown in FIG. 3, the box support comprises a pair of spaced side members or guides 20 beneath which are supported coil spring members 21, a side of which projects into the box path beneath the guides 20. The forward movement of the box B is limited by the adjustable stop members 23 which are carried by the spaced box guides 20. This construction is more fully described in the aforesaid Andresen Jr. et al. patent. The lower end of the plunger P is provided with a plunger form 25 preferably constructed from wood or other suitable material and having dimensions corresponding respectively to the length and width of the interior of the box B. As the plunger P moves downwardly, the form 25 is inserted into the interior of the box B and the coil springs 21 are adapted to be depressed along the length thereof corresponding to the length of the box B to compress the sponge rubber strip, not shown, thus permitting the box B and the form 25 to pass between the coil springs and down onto the adhesive-coated wrapper W on the upper surface of the perforated belt 27 of the suction conveyor C. It will be noted that prior to deposit of the box on the wrapper advancement of the wrapper W has been limited by the engagement of the leading end of the wrapper W with the end stop E.

When the box-wrapping system 10 is put into operation, by depressing a pedal 28, FIG. 1, the boxes B are moved along the box conveyor BC and BC until the leading box engages the stops 23, FIG. 3. At the same time the gluer G feeds adhesive-coated wrappers W to the suction conveyor C and they are advanced cyclically therealong until the leading wrapper engages the end stop E beneath the registering station R FIG. 3, The plunger P is reciprocated by means of a link 41 and an arm 41, the latter being adapted to be selectively driven by way of a clutch 42 from a driving shaft 43, FIGS. 1, 3 and 3A. Shaft 43 is rotated by a mechanism including a bellcrank 46, spring 47 and link 48 as in 'FIG. 8 of Patent 2,867,158. The driving shaft 43 is also adapted selectively to reciprocate the plunger P of the register device R by way of a selectively operable arm 45 and clutch 44 as later to be described in connection with tight-wrap work. The plunger arms 41 and 45, when disengaged by their respective clutch means 42 and 44 from the driving shaft 43 are held in their uppermost positions by suitable locking means such as pins p and p adapted to be inserted into openings in the plunger shafts as shown in FIG. 3. The clutch means 42 and 44 may be interconnected, as by a tube 43a on shaft '43, FIG. 3A, so that the engagement of one clutch will insure disengagement of the other and vice-versa, with an intermediate neutral position where both clutches are disengaged. The plunger P and its operating parts are supported by a bracket 49 secured to the front of wrapping machine W.

Referring to FIGS. 3 and 4, the end stop E for the wrapper comprises a pair of slotted fingers which are supported by collar members 31 carried by a rod 3 2 which extends transversely of the conveyor C. The ends of the rod 32 are supported by brackets 33 which, in turn, are secured to the frame of the conveyor C. The collars 3 1 are adapted to be adjustably secured to the rod 32 in fixed position by means of set screws 35. Set screws 36 also extend through slots in the fingers 30 and by adjustment of set screws and 36, the lower ends of fingers 30 are so positioned with respect to the upper surface of the conveyor belt 27 that they will just clear the upper surface of the conveyor belt, but will engage the leading edge of the wrapper W. It is important that this adjustment should be very precise in order to avoid wear on the conveyor belt 27.

As may be seen in FIG. 4, the box B has just been deposited on the wrapper W at the transfer station by plunger P FIG. 3. The plunger P has moved again to its upper position of FIG. 3 and the transfer mechanism T of the box-wrapping machine W has moved from the wrapping station of the wrapping machine over the transfer station to grip a box and wrapper assembly. The box-wrapping machine M is of the type shown in US. Patents 2,074,561 and 2,144,338 and includes an automatic transfer mechanism T generally similar to that described and claimed in US. Patent 2,705,905 with certain improvements as now to be described.

The transfer mechanism T comprises a pair of transfer members 50 having box-gripping fingers 51 (FIG. 4) pivotally supported at 52 at their forward ends and biased to gripping position by tension springs, not shown, The gripping fingers 51 cooperate to engage the rear corners of the box B and cooperate with front stops 53 to hold the box at the four corners. The front steps 53 also are carried by the transfer members 50 and are adjustable for different box sizes. The transfer members 50 are adapted to be reciprocated in side supports 54, which in turn are carried by the frame of the box-wrapping machine M. The rear ends of the transfer members 50 are connected by means of a carriage bar, not shown, which in turn is provided with bearing members adapted for reciprocation in carriage guides. The transfer mechanism T, as thus far described, corresponds to that disclosed in the aforesaid Lange et al. Patent 2,705,905. In the Lange et al. patent, the leading adhesive-coated flap of the wrapper was adapted to be engaged by suction members carried by the respective transfer members 50. The face of the suction members was provided with a surface of a polymer of tetrafluoroethylene marketed under the trademark Tefion or equivalent surface material to enable it to engage the adhesive on the leading flap without causing the adhesive to adhere to it. In the tight-wrap work, as disclosed in the aforesaid Lange et al., patent, it was only necessary for the suction members to support the leading flap of the wrapper during its transfer from the suction conveyor to the wrapping station of the box machine since the overall surface of the wrapper was coated with adhesive and thus the center of the wrapper was in adhesive engagement with the bottom of the box and thus adhered to the box at that area during transfer to the wrapping station.

In the present system, where it is desired to wrap loosewrap work, the wrapper only has adhesive around the edges of the flaps and the central area of the wrapper is free of adhesive. In view of this, the wrapper does not adhere to the box during transfer of the box and wrapper assembly from the transfer station to the wrapping station of the box machine and thus it is necessary that the wrapper be independently supported. In order to accomplish this, the transfer members 50 are provided with suction devices or members 56 which are especially constructed for vertical movement as a predetermined time during the transfer stroke of the transfer mechanism. This predetermined vertical movement is particularly important in order that the wrapper will clear the platen 57 beneath the form block F of the box-wrapping machine, FIG. 4 as now to be described.

Referring to FIGS. 6 and 7, it will be seen that the suction members 56 are connected by Way of a tube 60 to a hollow block 61 disposed within each of the transfer members 50. The block 61 is adjustable lengthwise of the transfer members 50, as by screws 62, in order to adjust the suction members 56 to accommodate different sizes of wrappers. The rear end of each block 61 is provided with a tube 63, FIG. 6, which extends through the transfer members 50 and connects at its rear end with suitable suction hoses, not shown. The suction members 56 comprise a vertical tube member 65 which has an opening through the Side wall thereof and is secured to the tube 60 as shown in FIG. 7. A second tubular member 66 is adapted to reciprocate vertically with the tube 65. The upper end of the inner tube 66 is provided with a plug or cap 67 to seal the upper end thereof and the lower end of tube 66 remains open and is provided with a suitable suction cup '68 preferably of an adhesive resistant material such as Teflon or equivalent. The lower surface of the transfer member 50 is provided with a layer of Teflon 69 to avoid the buildup of adhesive thereon as shown in FIG. 7. The inner tube member 66 is provided with a vertical slot 70 which is of substantially greater length than the diameter of the passage in tube 60 so as to maintain a constant suction path from suction member 56 through tube 60 to the suction connection to block 61 during any vertical movement of the inner tube 66 in the suction member 56. The inner tube member 66 is also provided with a pair of vertical slots 71 disposed in the opposite side walls thereof and at 90 from slot 70, only one slot 71 being shown in FIG. 7. The slots 71 are adapted to receive a cross pin 72 which extends therethrough and has its ends secured to the outer stationary tubular member 65. A compression spring 74 interconnects the cross pin 72 and the plug 67, FIG. 7. The slots 71 enable the pin 72 to pass through the side wall of the inner tube 66 and not interfere with its vertical movement when the plug 67 engages an operating cam 75.

As may be seen in FIGS. 4-7, each of the transfer mechanism supports 54 is provided with an arm 78 which in turn is provided with a slotted member 7 9 for supporting the operating cams 75 for the respective suction members '56. The operating cams 75 are carried by a pivot member 80 which extends through the slot 7 9s of member 79. The slots 79s provide for adjustment of the cams 75 for different sizes of wrappers. It will be noted that the upper end of each cam 75, FIG. 6, is provided with a flat surface 75a which is in engagement with the overlying plate member 81 which is secured to each member 79 as by screws 82. The plate members 8-1 provide a stop or limit for the counterclockwise rotation of the pivotallymounted operating cams 75.

The tranfser operation of a box and wrapper assembly from the transfer station of the suction conveyor C to the wrapping station of the box-wrapping machine M will now be described. In FIG. 4, the transfer mechanism T has moved over the end of the suction conveyor C at the transfer station to enable the gripping members 51 and 53 to grip the opposite corners of the box B. The box B is prevented from being pushed off of the conveyor C in a rearward direction by the rear box stops 85 which are adjustably supported on the frame of the conveyor C to accommodate different sizes of boxes. When the transfer mechanism T has moved to the position shown in FIG. 4 to pick up a box B and wrapper W, the suction members 56 engage the lower edge of earns 75 as shown in FIGS. 4 and 6 causing the suction members to be depressed to their full-line position as shown in FIG. 6 from their normally raised position shown in phantom-line. In the depressed position, the suction cups 68 at the lower open end of the suction members 56 are closely adjacent the adhesive-coated edge of the wrapper W and thus cause the wrapper W to be moved into engagement with the suction cups 63. The suction is sufliciently strong to hold the wrapper against the suction cups 68 and cause the wrapper to be raised therewith under the bias of the springs 74, FIG. 7, during the reverse movement of the transfer mechanism T. At this time the suction members 56 are retracted to the phantom-line position shown in FIG. 6 and they maintain this retracted or elevated position during the remainder of the transfer of the box and wrapper to the wrapping station beneath the form block F, FIGS. 4 and 5.

Since the suction members 56 provide the support for the leading flap of the wrapper as it moves ofi of the conveyor belt 27 of suction conveyor C, 'FIG. 5, it is necessary that the leading flap of the wrapper be prevented from sagging in order to insure that it will clear the platen 57. The required transfer movement of the wrapper without interference is insured by providing adequate suction to the suction members 56 and by enabling them to be retracted to a position well above the upper surface of the platen 57. It will be appreciated that this is particularly important when wrapping relatively large boxes since the weigth of the wrapper will be substantial and the tendency to sag will be increased. It will further be apreciated that if the wrapper were to engage the platen 57 during the transfer of the box and wrapper assembly, the wrapper would be damaged and the box could not be wrapped properly. In view of the fact that this is an automatic box-wrapping system and speed of operation is highly important, it is imperative that such faulty operation not occur, as it would require shutting down the entire system.

Referring again to FIG. 4, it will be seen that the operating cams 75 for the suction members 56 extend over the top of the box B. When the box is of a size having substantial depth, the box corners will engage the lower ends of the cams 75 but the box will pass under the cams 75 during transfer since the earns 75 are pivotally mounted at 80. However, the transfer mechanism T operates at a relatively high speed and the engagement of the box corners with the cams 75 tends to cause the box to tilt in the transfer mechanism and thus the box will be in a tilted position when it is beneath the form block F, FIG. 4. This can not be tolerated as the form block F must be able to enter the box and clamp the bottom of it against the platen 57 as described in the aforesaid patents. In order to eliminate this problem, which is only present on deep boxes, the pivotal earns 75 are provided with cylindrical projections 87, FIGS. 4, 6 and 7 which extend outwardly of the earns 75. These projections 87 will engage the upper edge of the end walls of the deep boxes and thus cause the box to be returned to its normal horizontal position rather than remaining in a tilted position as mentioned above. This insures that all of the side and end walls of the boxes will be in perfect vertical position beneath the form block F and thus avoid any damage to the boxes as would otherwise occur if the walls were in a tilted or non-vertical position.

While the above description has been primarily concerned with loose-wrap work, it is to be understood that the present system is equally applicable to wrapping tightwrap work. For tight-wrap work, the system 10 may be operated in similar manner to that described in the aforesaid Andresen Jr. et a1. Patent 2,867,158. All that is necessary is to disable the plunger P at the register station R by uncoupling clutch 42, FIG. 1, and bringing plunger P of the first registering station R into operation by coupling of clutch 44. In addition, the box stops 23 of FIG. 3 are removed from registering station R and placed on the corresponding box rails 26a at registering station R. The chain drive 15 is disconnected from the box extension conveyor BC The gluer G is adjusted to provide an overall adhesive coat on each of the wrappers W and thus when a box B is placed on the adhesivecoated surface of the Wrapper W, it will adhere thereto, and the resulting assembly of a box and partially applied wrapper will be transported along the suction conveyor C from the registering station R to the transfer station at the end of conveyor C opposite the box-wrapping machine M. This is the preferred operation of the system for tight-wrap work since it is desirable to place the setup box B on the adhesive-coated wrapper as early as possible during the transit of the wrappers along the suction conveyor in order to insure accuracy of alignment of the box and wrapper.

However, under certain conditions, and particularly for certain types of wrapper material, it is sometimes desirable for the adhesive to have an opportunity to penetrate the wrapper before the set-up box is placed thereon. Under these conditions, it is possible to wrap the tight-wrap work in the same manner as the loose-wrap work by depositing the box on the wrapper at the second registering station R rather than at the first registering station R.

While a preferred embodiment of this invention has been described and illustrated, it shall be understood that the invention is not limited to the specific arrangements shown and that changes and modifications may be made within the scope of the appended claims.

What is claimed is:

1. An automatic box-wrapping system for loose-wrap work comprising box conveyor means for cyclically moving set-up boxes along a path, stop means for interrupting the movement of the boxes at a predetermined location on said path above a transfer station, wrapper conveyor means for cyclically feeding wrappers in succession below and in a path parallel to that of said box conveyor means, said wrappers having unset adhesive along the edges of their upper surface, means extending over said wrapper conveyor means for interrupting the feeding movement of the wrappers at the transfer station, vertically reciprocating means movable between the predetermined location and the transfer station for moving said boxes in succession downwardly into register with corresponding wrappers, a Wrapping station at one side of said transfer station, and transfer means movable transversely of both of said conveyor means at said transfer station for transferring each box and wrapper in registered relation from the transfer station to said wrapping station for application of the adhesive-coated wrapper to the box.

2. An automatic box-wrapping system according to claim 1 wherein said transfer means includes a pair of spaced arms having stnicture thereon for gripping the set-up box, and vertically movable suction means disposed on said arms for gripping the wrapper, means for moving said vacuum means downwardly into engagement with the wrapper at the transfer station and means for thereafter raising said suction means for lifting the wrapper to a higher plane during transfer to the wrapping station.

3. An automatic box-wrapping system according to claim 1 wherein said transfer means includes a pair of spaced arms having structure thereon for gripping the setup box, and vertically movable suction means disposed on said arms for gripping the wrapper, cam means engaged by said suction means when said transfer arms are at said transfer station for moving said suction means downwardly into engagement with the wrapper at the transfer station, and means for thereafter raising said suction means for lifting the leading flaps of the wrapper to a higher plane during transfer to the wrapping station.

4. An automatic box-wrapping system according to claim 1 wherein said means for interrupting the movement of the wrappers at the transfer station comprises a pair of elongated members adjustable transversely and longitudinally of said wrapper conveyor means in accordance with the size of the wrapper to be applied to the setup box, and means for locking said elongated members in fixed position above the upper surface of said wrapper conveyor means with one of their ends positioned slightly above but sufficiently close to the upper surface of said wrapper conveyor means to engage the leading end of the wrapper as it lies flat on the conveyor and interrupt its movement at a predetermined position at said transfer station.

5. An automatic box-wrapping system comprising conveyor means for moving set-up boxes along a path, stop means for interrupting the movement of the boxes at a predetermined location on said path, means for cyclically feeding adhesive-coated wrappers in succession along a path that is parallel to and below said box conveyor and leads to said predetermined location, means for interrupting the movement of the wrappers each time the center lines of a wrapper are in alignment with and below the center lines of a box at said predetermined location, reciprocating means for moving said boxes in succession downwardly into register with corresponding wrappers to form assemblies of box structure and wrappers, a wrapping station at one side of said transfer station, and transfer means movable transversely of said path at said predetermined location for transferring assemblies of a box and wrapper in succession from the transfer station to said wrapping station for application of the adhesivecoated wrapper to the box.

References Cited in the file of this patent UNITED STATES PATENTS 2,152,775 Stokes Apr. 4, 1939 2,867,158 Andresen et a1. Jan. 6, 1959 2,958,267 Wolff et al Nov. 1, 1960 2,961,931 Von Hofe et al. Nov. 29, 1960 

